Pressure gauges are utilized in a wide variety of applications and environments for the measurement of fluid pressure. Typically, the installation of such gauges can vary from virtually calm fluid conditions in which the fluid being measured is pulsation free to a high frequency pulsing fluid as might be encountered for example from a reciprocating pump or compressor. To enable connection of a pulsating condition to the pressure gauge, it has been known to utilize a helical flow path of sorts such as afforded by a screw thread contained in a bore communicating with the inlet of the gauge. The helical flow path defined by the thread effectively throttles the pulsations and avoids their being transmitted to the sensing elements of the gauge. A pulsation dampener of the type described is disclosed for example in U.S. Pat. No. 1,162,982 to Crocker.
While the prior art pulsation dampeners of the type disclosed in the Crocker patent supra are effective for achieving the desired dampening effect, they are generally characterized by a relatively small continuous flow path of uniform cross-sectional dimension from inlet to outlet. In that arrangement, any particle of dirt or whatever contained in the fluid of size larger than the minimum cross section of the defined flow path tends to lodge in the flow path to effectively plug it thereat and eventually render the pressure gauge inoperative. Obviously, the extent to which plugging may occur will vary with the condition being encountered, but because of the potential plugging problem, it has been common to either provide a fine screen filter upstream of the dampener or tolerate the plugging problem as a maintenance item. Either of the foregoing has been regarded as less than satisfactory.